diff --git a/man/systemd.network.xml b/man/systemd.network.xml
index 58dae4f948..4c777ef4e0 100644
--- a/man/systemd.network.xml
+++ b/man/systemd.network.xml
@@ -2382,9 +2382,12 @@ MultiPathRoute=2001:db8::1@eth0
When true (the default), the machine's hostname (or the value specified with
Hostname=, described below) will be sent to the DHCP server. Note that the
- hostname must consist only of 7-bit ASCII lower-case characters and no spaces or dots, and be
- formatted as a valid DNS domain name. Otherwise, the hostname is not sent even if this option
- is true.
+ hostname must consist only of 7-bit ASCII lower-case characters and no spaces, and be
+ formatted as a valid DNS domain name. A single-label hostname is sent as DHCP option 12
+ (Host Name, RFC 2132);
+ a multi-label hostname (FQDN) is sent instead as DHCP option 81 (Client FQDN,
+ RFC 4702).
+ Otherwise, the hostname is not sent even if this option is true.
@@ -2395,7 +2398,8 @@ MultiPathRoute=2001:db8::1@eth0
Use this value for the hostname which is sent to the DHCP server, instead of machine's
hostname. Note that the specified hostname must consist only of 7-bit ASCII lower-case
- characters and no spaces or dots, and be formatted as a valid DNS domain name.
+ characters and no spaces, and be formatted as a valid DNS domain name. Multi-label hostnames
+ (FQDNs) are acceptable; see SendHostname= above for details.